W Hi Pressure-Flow Plunger
 Key
Features
STANDARD MATERIALS:
- Wetted parts - 316 SS
- Plunger - 316 SS
- Controller - MK-X - 316 SS
- Relays - 316 SS
SEAL MATERIALS:
- Teflon Graphite (TG) for pressures of 1000 to 10,000 PSIG
- O-Ring seals are available for pressures below 900 PSIG in
various materials, K-Kalrez®, V-Viton® and BR-Buna
N, EPR-Ethylene Propylene.
VISCOSITY:
- Maximum recommended viscosity 4500 SSU (Saybolt Seconds Universal)
or 960 CP (Centipoise).
 Operation 
POWER STROKE:
As the supply air/gas from the CONTROLLER-RELAY enters the PNEUMATIC
DRIVE CYLINDER thru the POWER STROKE PORT, the PISTON-PLUNGER ASSEMBLY
is driven down into the FLUID CYLINDER, displacing fluid. The fluid
displacement results in an increase in pressure which closes the SUCTION
CHECK VALVE and opens the DISCHARGE CHECK VALVE. A precise amount of
fluid, corresponding to the stroke of the plunger, is discharged.
SUCTION STROKE:
When the air/gas is exhausted from the top portion of the PNEUMATIC DRIVE
CYLINDER through the CONTROLLER-RELAY, air/gas is then supplied to
the bottom portion of the PNEUMATIC DRIVE CYLINDER in order to return
the PISTON-PLUNGER to its original position. The drop in pressure caused
by the retraction of the PISTON-PLUNGER assembly allows the DISCHARGE
CHECK VALVE to close, and the SUCTION CHECK VALVE to open. The FLUID
CHAMBER is then refilled and ready for the POWER STROKE.
 Design
Philosophy
The Williams "W" Series pneumatic metering pumps are engineered
for PERFORMANCE, QUALITY, SAFETY and SIMPLICITY.
PERFORMANCE
ACCURACY Our positive displacement plunger pumps can provide accuracies
to ±.5% satisfying API-675.
FLOW TURNDOWN
Since our metering pumps offer both stroke rate and stroke
length adjustment, flow turndown ratios as great as 100:1 can be achieved
exceeding the API-675 requirement.
PRESSURE
Because of the large area difference between the air/gas piston
and the plunger, our pumps can produce 3,450 PSI (238 BAR) with only
150 PSI (10.3 BAR) of air/gas supply pressure.
CORROSION RESISTANCE
We have selected materials, such as 316 SS, elgiloy,
TFE, etc., for both wetted and non wetted parts, that afford the maximum
corrosion resistance. These materials satisfy the requirements of such
organizations as NACE and the FDA.
QUALITY
TESTING All pumps are performance tested prior to shipment.
RELIABILITY
Our quality assurance program insures the optimum in product
performance and life by controlling the products configuration through
all stages of design, engineering, production, assembly and test.
WARRANTY
We warranty both performance and manufacturing defects.
SAFETY
PNEUMATICS Unlike electrics, pneumatics provides an intrinsically safe
design at no extra cost.
MATERIALS
The corrosion resistant materials used in the entire pump
minimize the damage that could occur during a chemical spill.
LOCATION
Pneumatics and corrosion resistant materials allow our products
to be used in harsh environments where wet/corrosive vapors or salt air
is present.
SIMPLICITY
SIZE The pneumatic design concept provides a compact design much smaller
than the comparable electrically driven pump.
INSTALLATION
The compact design allows the pumps to be installed directly
in the piping with minimum support, thus eliminating the need for concrete
mounting pads.
MAINTENANCE
The pneumatic design approach limits the number of parts
thus simplifying and minimizing maintenance.
 Application
When sizing and applying Williams plunger pumps please use the following
information to guide your selection:
PLEASE NOTE THAT OUR PLUNGER PUMPS HAVE PRESSURE-ACTIVATED SEALS. THEY
SHOULD NOT BE USED AT PRESSURES BELOW 100 PSI.
STROKE RATE AND LENGTH
Even though the pumps are designed to operate over their entire stroke
rate and length ranges, we suggest that you take into consideration
your future flow requirements. Rather than operating at the flow extremes
you may wish to use the next pump size larger or smaller.
FILTRATION
Plunger pumps are susceptible to contamination. Therefore we recommend
a 25 micron filter in the suction line of the pump.
SUCTION CONDITIONS
The W Series plunger pumps are designed for flooded suction only. They
are NOT recommended for a suction lift condition. The recommended pressure
at the suction inlet is:
1 ft. (.3 meters) min. * 10 ft. (3 meters) max.
NOTE: The normal cracking pressure of the discharge check valve is 90
PSI.
VISCOSITY
The maximum recommended viscosity is 4500 SSU (Saybolt Seconds Universal)
or 960 CP (Centipoise).
FLOW TURNDOWN RATIO: 100:1
NOTE: The flow turndown ratio is defined as the total flow range of the
pump, which includes both speed and stroke length adjustments.
ACCURACY
± 0.5% with Solenoid Valve and WPC-9001 ± 1.5% with MK-X
Controller
TEMPERATURE
The seals are the limiting factor. Please refer to the seal selection
guide for temperature limits.
AIR/GAS SUPPLY
The air/gas supply must always be regulated since fluctuating pressures
will affect speed and accuracy. The air/gas must be free from particulate
and we recommend dry air/gas for trouble free operation.
PUMP SETTING GAUGE
We recommend the use of a pump setting gauge as a simple method of adjusting
the flow of the pump.
DISCHARGE LINE CHECK VALVE
It is good design practice to install a check valve in the pump discharge
line at the point it enters the process line. This will prevent the
process fluid from reaching the pump.
AMPLIFICATION RATIO
The amplification ratio is the area difference between the air piston
and the fluid plunger.
To ensure a longer operational life of the pump, it is important not
to use a greater air supply pressure than is necessary to provide positive
chemical injection. Assuming a specific amplification ratio, the air
supply pressure must be regulated to ensure that the pump discharge pressure
is greater than the process pressure. In calculating the proper air supply
pressure, add 200 PSI (13.8 BAR) to the process pressure, then divide
by the amplification ratio.
EXAMPLE:
Assume a process pressure of 2800 PSI (193 BAR) (process pressure
is the pressure into which the chemical is injected).
Add 200 PSI to the process pressure so that the chemical is positively
injected: 2800 PSI + 200 PSI = 3000 PSI (193 BAR + 13.8 BAR = 206.8 BAR).
Assume using a Williams pump with an amplification ratio of 23:1 (implies
that for every 1 PSI (1 BAR) input pressure, the pump produces 23 PSI
(23 BAR) output pressure).
Supply of air or gas pressure to controller is: 3000 ÷ 23 = 130
PSI (206.8 BAR ÷ 23 = 9 BAR).
Viton® is a registered tradmeark of DuPont Dow Elastomers L. L.
C.
 Literature
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